This invention relates to lighting fixtures. More particularly it relates to lighting fixtures for use in overhead lighting.
Existing light fixtures for overhead lighting in commercial and retail applications typically use fluorescent lamps for a number of reasons relating to maintenance, energy efficiency and lighting capabilities. In all of these areas, fluorescent lights have advantages over incandescent lights. In such retail and commercial applications the ceiling is typically of a suspended ceiling configuration using suspended T-bars arranged in a gridwork for hanging ceiling panels. Light fixtures for use in such ceilings are typically sized to fit within the gridwork of the T-bars. A typical suspended ceiling will have grids formed by the suspended T-bars with each grid section being two foot by four foot. Conventional fluorescent light fixtures are typically sized to fit within such grids. Such traditional fixtures usually have a box shaped housing with a separate upper chamber that contains the ballast and wiring. The chamber is typically substantially the same length and width as the fixture. Due to the general box shape configuration of conventional fixtures the chamber is greatly oversized at least insofar as what is required for containing the ballast.
The fluorescent lamps are typically mounted within the fixtures below the chamber housing the ballast. Typically a transparent plastic panel or louvers will be mounted on the open bottom end of said fixtures, positioned between the bulbs and the space to be lit. Such louvers or transparent panels function to temper the intensity of the light emitting from the fluorescent tubes when looking directly at the fixture. Such louvers or transparent panels also necessarily decrease the efficiency of the light transmission of the fixtures.
The typical fluorescent ceiling light fixture utilizes four fluorescent lamps placed in a parallel arrangement in a horizontal plane within the fixture. Such conventional fixtures also typically utilize a painted white panel for a reflector immediately above the fluorescent tubes. Said panel may also be the bottom panel for the chamber containing the ballast.
Due to the size and weight of said light fixtures, it is typically a two-man operation to place the light fixtures in the suspended ceiling grid. Moreover, the location of the relatively heavy ballast at the top of the box structure creates a high center of gravity lending towards awkwardness in handling these structures.